We absolutely use time out for that sort of behavior and if she followed us out we put up a baby gate. It will only get worse when they new baby arrives and needs to be nipped in the bud now. Two year olds love control and when they don't have it they lose control of themselves. The answer is not to give them more control. That just makes them feel overwhelmed. Give her simple choices and when she starts to have a fit, put her in a designated place to clam down (time out). When she's calm say something short and to the point, "There is no yelling at Mommy." Hugs and its over. Talking too much can restart the cycle. She'll still have fits, but being firm with her will teach her that screaming doesn't get her what she wants.